Apparatus for making extensible retractile cords



y 1945- c. .1. HACKBARTH 2,377,003

APPARATUS FOR MAKING EXTENSIBLE RETRACTILE CORDS Filed July 25, 1942 /N l/E'NTO/Q CJ H CKBHETH BY 1477' NE) Patented May 29, 1945 APPARATUS roa MAKING EXTENSI'BLE RETRACTILE- CORDS Carl J. Hackbarth, Baltimore, Md., assignor :to

Western Electric Company, Incorporated, New "York, N. Y., a corporationofNew York Application July 25, 1942, Serial No. 452,303

' *1 Claims. (01. 37-34) This invention relates to apparatus for making extensible retractile cords.

'IIn the manufacture of extensible retractile cords 'the conductors which comprise one of the cords are sometimes formed at spaced intervals intoloops positioned outside of the braided covering which encloses the cord. Such loops are .laterseveredto permit the application of electrical connectors to the cords. 'Io permit these conductors to be readily formed into loops, it

is necessary that whatever means is employed to position the conductors within the braided covering or to soften the braid of the covering upon the conductors .be placed internally of the "cord among the conductors.

Objects of this invention are to provide new and efiective apparatus for making extensible retractile cords, and more particularly to provide new and improved apparatusior impart ing an inherent tendency to bend to conductors:

.An apparatus embodying this invention comprises means for braiding a covering about a plurality of strands, and a member disposed between certain of the strands and the other strands While'the braided covering is being applied about thestrands. I

Other features and advantages of the invention will become apparent from the following detailed description of one embodiment thereof when read in conjunction with the accompanying drawing, in which i Fig. 1 is a vertical sectional view of a portion of .an apparatus for making an extensible re-' "tractile cord;

Fig. 2 is a horizontal sectional view thereof taken on line 2--2 of Fig. 1;

Fig. 3 is an enlarged sectional view taken on line 3-3 of Fig. 1, showing a cross-section of a cord being made by the apparatus and of a guide member forming part of this apparatus; Fig. 4 is a top plan view of the guide member shown in cross-section in Fig. 3;

Fig. 5 is a side elevation of the guide member, and 4 .Fig. .6 is an enlarged sectional view of a guide member constituting an alternative embodiment of theinvention.

In the particular embodiment of the invention disclosed in the accompanying drawing, three conductors H), II and. I2 arev passed upwardly through a braider head I 4 of a suitable type known in the art. A cross piece l5 (Fig. 2) is fastened ,to a shoulder it formed in the braider "headllzandsupports a guide member l8 (Fig. 5) which is located centrally within the braiderss .a 'coil. By braiding the-covering 32 over the head I. The guide member It comprises an elongated post IS in which a U-shaped channel 20 and guide grooves 2| and 22 are formed. An enlarged cylindrical head 24 is formed upon the guide member l8 between the elongated post l9 and a threaded portion 25. The threaded portion 25 is inserted through an aperture 23 in the cross piece l5 and is fastened therein by means of a nut 26. Spaced notches 28, 29 and '30 (Fig. 4) are formed in thecylindrica'l head for guiding the conductors H), II and I2.

The conductors I 0, H and I2 are'held inthe U-shaped channel 20 and the guide grooves 2| and 22, respectively, by yarn strands .3 |--3l which are interbraided about the conductor to form a braided covering 32 thereon. The covered conductors are drawn upwardly and then over and around a cylindrical capstan 34 to form the-finished cord into a coil, and the cord is so positioned that the two conductors I l and I2 lie substantially against the outer periphery of the capstan 34, while the third conductor in lies radially outward therefrom. Due to this arrangement it will be seen that the outer conductor Ill forms a convolution of greater diameter than those of the inner conductors II and i2 and, consequently, is longer than the inner conductors. In order to permit this formationjthe outer conductor I!) must be advanced through "the apparatus at a greater .speed than that of the inner conductors II and 12. l i

This is possible in the apparatus embodying the invention because the U-shaped channel 20' formed in the post l9 has a depth approximately equal to the diameter of the conductor 11:0, so that the conductor I0 contacts the braided covering 32 on only a very small-portion of its periphery andthus is relatively free to move within the covering 32. Also, the post l9 entirely separates the conductor l0 from the conductors II and i2 and permits the conductor Io to move freely relative to the other conductors l l and I2. Since the conductor ID has a greater length than the inner conductors H and i2, the cord has a natural tendency to form a helical coil. After the braided coveringhas passed beyond the upper end of the post l9, it contacts all of the conductors and holds them together so that there is 'no slippage between the braid and the conductors.

The guide member l8 also serves the additional function of softening the braided covering 32 which might otherwise be applied too tightly to the :cord to permit it'to be readily formed 'into conductors H], H and I2 while they are separated by the post IS, the withdrawal of the braided covering from the guide member 3 tends to loosen or soften the braid of the covering of I the cord and permits the cord to readily assume a helical shape about the capstan 34.

When it is desired "to form loops in the conductors making up the retractile cords, the braiding machine is stopped and uncovered portions of the conductors are withdrawn from beneath the portions thereof covered by the covering 32 and pulled outwardly away from the post [9. If such loops are to be made rapidly and easily, the conductors must be free to move outwardly without restriction. The post I9 is so constructed that the conductors passing thereby may be freely drawn outwardly to form loops therein because there is no portion of the post If] which is outside of the conductors. The conductors are advanced along the channel 28 and the grooves 21 and 22, as shown in Fig. 3, and it is obvious from an examination of Fig 2 that there is nothing to interfere with the withdrawal of the conductors when it is desired to form loops therein.

Fig. 6 illustrates an alternative embodiment of the invention comprising a post H9 having a U-shaped channel 82!). The post HS is identical with the post It. except that the channel [2c is wide enough to partially enclose two conductors ll0l it, while the channel 2!] is wide enough to enclose only the single conductor iii. The post H9 is provided with grooves 524 and H2, which are similar to grooves 2| and 22, respectively, and serves to separate the conductors Elli-l Hi from conductors III and H2 as a covering i32 is braided over the several conductors.

The post H9 holds the covering I32 substantially out of contact with the conductors I lil-l l0 and separates completely the conductors l l3-l ill from the conductors Hi and 122. Thus, the conductors lid-E H] are not retarded by frictional engagement with either the covering IE2 or the conductors H! and H2, and the conductors llll ilil are free to advance more rapidly toward the capstan than are the other conductors.

What is claimed is:

1. In a braiding machine for a cord, means for supplying three conductors to be covered with braid, spaced guides for positioning the conductors, a cylindrical take-up capstan for receiving the conductors with two of the conductors adjacent to the capstan and the third conductor spaced radially outwardly from the first two conductors, and means disposed among the conductors and substantially entirely around said third conductor for causing said third conductor to be supplied at'a faster rate than the first two conductors.

2. In an apparatus for forming retractile cords, means for braiding a covering around a plurality of insulated conductors, a cylindrical capstan for withdrawing the covered conductors from the braiding means and for winding them in a helical form with some of the conductors adja* cent to the capstan and another of the conductors separated from the capstan by the firstmentioned conductors, and a U-shaped guide member positioned so that the conductor that will be the furthest removed from the capstan will rest within the member and will be separated by the member from the other conductors, the U-shaped member being of sufiicient size to prevent substantial contact between the conductor positionedtherein and the braided covering formed around the group of conductors, whereby the conductor positioned in the U-shaped member may be advanced at a faster rate than the other conductors.

3. In an apparatus for forming retractile cords, means for forming a covering around three conductors, a capstan on which the covered conductors are helically wound with two of the conductors lying adjacent thereto and the third conductor separated from the capstan by the two adjacent conductors, and means positioned within the covering means and adjacent to the capill) (ill

4. In an apparatus for forming retractile cords, I

means for supplying at least three conductors to be covered with a braided covering, means for braiding a covering around all of such conductors, a cylindrical take-up capstan serving to receive two of the conductors adjacent thereto and the remainder of the conductors spaced radially outwardly from said two first-mentioned conductors, and means disposed among the conductors and substantially entirely around any of the conductors spaced radially outwardly from said two conductors, whereby any conductor enclosed by said last-mentioned means is separated from said two first-mentioned conductors and from a covering applied by the braiding means over all the conductors.

5. In an apparatus for forming retractile cords, means for supplying four conductors to be covered wit a braid, means for braiding a COVelll'ig around the conductors, a cylindrical capstan serving to withdraw the covered conductors from the braiding means and to wind them in a helical form with two of the conductors adjacent to the capstan and the other two conductors separated from the capstan by the first-mentioned conductors, and a U-shaped guide member positioned so that the conductors which will be removed farthest from the capstan will rest within the member and will be separated from the other conductors, the U-shaped member being sufiiciently deep to prevent substantial contact between the conductors positioned therein and a covering braided around all of the conductors, whereby the conductors positioned in the U-shaped member may be advanced at a faster rate of speed than the other conductors and the braided covering.

6. In an apparatus for forming retractile cords, means for supplying at least three conductors to be covered with a braided covering, means for braiding a covering around all of such conductors, a cylindrical take-up capstan serving to withdraw the covered conductors from the braiding means and to wind them thereon in a helical form with at least two of the conductors adjacent to the capstan and at least one of the conductors separated from the capstan by' said first-mentioncd conductors, whereby the conductors adjacent to the capstan are shorter than any other of the conductors, and a guide member positoned between the shorter conductors and any longer conductor and having a U-shaped channel serving to substantially enclose any longer conductor, said channel being substantially equal outwardly from said two first-mentioned con-- in depth to the diameter of a conductor enclosed therein, and being positioned with the mouth thereof facing away from the shorter conductors, whereby the guide member completely separates any conductor enclosed therein from the shorter conductors and holds a covering braided over all the conductors substantially out of contact with any conductor enclosed therein 50 that the latter may be advanced at a greater rate of speed than the shorter conductors.

7. In an apparatus for forming retractile cords, means for supplying three conductors to be covered with a braided covering, means for braiding a covering around all of such conductors, a cylindrical take-up capstan serving to withdraw the conductors and a covering braided thereon from the braiding means and to wind them in a helical form with two of the conductors adjacent thereto and the third conductor spaced radially ductors, and a guide member positioned among the conductors and provided with a U-shaped channel substantially equal in depth to the diameter of the third conductor for separating the third conductor from the two first-mentioned conductors, said guide member substantially enclosing the third conductor and being positioned with the mouth of the channel facing away from the two first-mentioned conductors, whereby the guide member completely separates the third conductor from the two first-mentioned conductors and holds a covering braided over all the conductors substantially out of contact with the third conductor so that the third conductor may be advanced at a greater rate of speed than the two first-mentioned conductors.

CARL J. HACKBARTH. 

